 function doImgCenter(dom) {

     doPos(dom);

     function doPos(obj) {
         var iview = document.documentElement.clientWidth || document.body.clientWidth;
         if (iview > 1000) {
             obj.style.left = (iview - parseInt(obj.getAttribute("width"))) / 2 + "px";
         }
     }
     window.onresize = function() {
         doPos(dom);
     };


 }
